Stretcher-frame.



c. P. FREESTATE.

STRETGHEB. FRAME. APPLICATION FILED JAN. 13, 1908.

914,261. Patented Mar. 2, 1909.

CHARLES P. FREESTATE, OF CHICAGO, ILLINOIS.

STRETCHER-FRAME Specification of Letters Patent.

Patented March 2, 1909.

Application filed January 13, 1908. Serial No. 0,575.

To all whom it may concern:

Be it known that I, Cnr-lnLEs P. Flinn- STATE, a citizen of the United States of America, and a resident of Chicago, county of Cook, State of Illinois, have invented certain new and useful Improvements in Stretcher- Framos, of which the following is a specification.

The main objects of this invention are to provide an improved form of stretcher frame particularly adapted for stretching shade cloth during the operations of sizing and painting it; to provide an improved con struction whereby the rails of such frames may be constructed entirely of metal, thereby greatly reducing the fire risk in a shade cloth manufacturing plant; to provide a structure of this character which is practically free from parts which are likely to get out of order; to provide a type of stretcher rail to which the cloth may be readily clamped and in which the gripping faces of the clamping members are so arranged as to be protected from accumulations of sizing and paint, and in which the act of shifting the gripping surfaces into and out of engagement with each other will tend to spring the parts slightly so as to chip off any accumulations of paint and sizing which may have dried upon the outer surfaces thereof; to provide improved means for mounting a series of short clamping bars to a main bar; and to provide an improved method of hanging a stretcher frame, having a channel-shaped sheet metal rail, so as to prevent the weight of the parts from spreading the flanges thereof. These objects are accomplished by the device shown in the accompanying drawings, in which Figural is a partial front elevation of a stretcher frame constructed according to this invention and showing the cloth in position thereon. Fig. 2 is a rear elevation of the same, illustrating the advantages of the hinged lower rail. Fig. 3 is a transverse section of the upper rail, showing the method of clamping the cloth thereon and of retaining the bars in interlocking engagement with each other. Fig. 4 is a transverse section of the main bar of the upper rail, showing the method of connecting the hangers thereto. Fig. 5 is a transverse section of the upper rail, showing the clamp in its open position and showing the method of guiding the clamping bar on the main bar. Fig. 6 is a sectional detail of the clamping bar, showing its gripping surface faced with friction material, such as I rubber, to prevent slipping of the cloth. Fig. l 7 is a detail of the lower end of one of the toggle braces, illustrating the arrangement of the stud recesses for adjusting the brace. Fig. 8 is an enlarged detail of the hinge oint in the lower bar.

In the form shown in the drawings, the stretcher frame comprises an upper rail 1 provided with hangers 2 for supporting it in a substantially horizontal position and a second rail 3 connected with the upper rail 1 by means of a plurality of toggle braces 4, the whole frame being suspended in a substantially vertical plane by means of said hangers 2. Each of the rails is provided with clamping means for attaching thereto the edges of the sheet which is to be stretched. The upper rail 1 is preferably continuous throughout its entire length, while the lower rail is preferably divided into sections of convenient length, the ends of adjacent sections being hinged together on axes transverse to the plane of the frame. The hinges are indicated at 5 in the drawings.

In the form shown, the entire frame is constructed of metal. The upper rail 1 consists of a main bar 6, preferably formed of resilient sheet metal, bent to channel-shaped transverse section, as illustrated in Figs. 3 to 5, inclusive, and having mounted thereon a series of clamping bars 7 which are of short len th and also preferably of channelshaped cross-section. This shape of crosssection permits the bars to be made of comparatively light metal without sacrificing rigidity. The clamping jaws, by means of which the cloth is secured to the upper rail, comprise the lower shoulders or flanges 8 and 9 of the bars 6 and 7, respectively. The flange 9 of the bar 7 is referably bent to an acute angle with the we of said bar, and the flange 8 is bent to such angle with its web that it will lie parallel with the flange 9 when said jaw: are in gripp ng relation, as in Fig. 3. The flange 8 is also bent along a longitudinal line so as to extend upwardly a short distance along the faces of the bars 7 and provide an edge 10 about which the cloth 11 is folded, as in Fig. 3. This edge 10 also serves as a convenient guide along which the cloth may be torn when removing it from the stretcher frame.

In order to provide convenient means for retaining the bars in gripping engagement with the cloth, the upper flange 12 of the bar 6 is curved inward, and its edge forms a yielding shoulder which may be sprung over the top of the bars 7, as inFig. 3. To this end, the upper flange 13 of each bar 7 is inclined inwardly as illustrated in Figs. 3 and 5 5, so as to wedge the flange 12 outward when the bar 7 is pushed into position between the flanges of the bar 6. The upper flange of each bar 7 is offset either along a continuous line or at suitable intervals, to pro- 10 .Vide a, shoulder or shoulders 14 over which the edge of the flange 12 may be passed to retain the bar 7 in its gripping position.

In order to permit the bars 7 to freely move into and out of gripping position in- 15 dependently of each other, and thereby admit of local adjustment of the cloth, each bar 7 is separately connected to the main bar 6 by guide rods 15 Which pass through apertures in the lower flange 9 of the corresponding bar 7. The guide rods 15 are disposed at right angles to the length of the rail. The bar 7 is supported inits open position by means of lugs 16 which extend downwardly from the flange 13 and rest upon the top of the flange 12, as in Fig. 5.

The lower rail 3 has a transverse section exactly like that of the upper rail, with the exception that it is inverted so as to grip the cloth along the upper edge of the rail, and

the lugs 16 are also unnecessary on the clamping bars 7 of the lower rail, as said bars will tend to hang. in their open position when not engaged by the flange 12.

The toggle braces 4 are each constructed of two bars, the longer bar 17 being preferably of channel-shaped cross-section, and the shorter bar 18 being of angle section. The pivot 19 at the joint between the bars is located slightly out of line with the pivot 20 on the upper bar and the stud 21 on the lower bar when the toggle is in its expanded position, as shown in Fig. 2. The lower end of the bar 17 is provided with a longitudinal slot 22 and a plurality of branch recesses 23,

into either of. which the stud 21 may be seated for determining the spacing between the rails 1 and 3. The stud 21 is headed so as to prevent the bar 17 from slipping off from it.

The hangers 2 are provided with shanks 24 which extend downwardly through the upper flange 12 of the bar 6 of the upper rail an are riveted into the lower flange 8. The weight of the apparatus is thus carried in a manner which does not tendv to spread apart the flanges of the bar 6.

To permit the bars 7 to be readily released from gripping engagement, each is provided with one or more lugs 25 which serve as handles for pulling the shoulders 14 away from the flange 12.

The operation of the device shown is as follows :-All of the studs 21 are seated in corresponding recesses 23 of their braces 4 so that t e bar 3 hangs in a certain fixed relation to the bar 1, corresponding, of course, to the width of the cloth. The operator then passes along the frame, fastening the upper edge of the cloth into the rail 1 by successively moving into gripping position the bars 7 as he unrolls the cloth from a roll. The upper edge of the cloth is first laid over the edge 10 of the flange 8 of the upper rail, and the bars 7 are dropped from their elevated position and pressed into position between the flanges of the bar .6 so that the flange 12 passes over the shoulders 14. After reaching the end of the frame, the operator fastens the lower edge of the cloth into the lower rail 3 as he passes back along the frame. After both edges of so the cloth are attached to the frame, the braces 4 are detached from the lower rail and hung up on hooks 26, conveniently located on the rail 1. Sizing is now applied to the cloth and, while the cloth is still wet, the toggle braces are dropped from their hooks, and the studs 21 are each seated in the proper recess 23, to give the desired amount of stretching to the cloth when the braces are set up. The braces force apart the rails 1 and 3, and the cloth is thus stretched taut. The hinge joints in the lower rail permit each toggle brace 4 to be separately adjusted and set u as the operator passes along the frame, as W1 1 be understood from Fig.

I/Vhat I claim as my invention and desire to secure by Letters Patent is:

1. In a stretcher frame, a rail formed of two parallel bars having co-acting gripping faces at adjacent longitudinal edges, one of said bars aving thereon resilient means adapted to be sprung. into engagement with said other bar for retaining said gripping faces in clamping engagement, a second rail, and means adapted to force said rails apart to stretch a sheet of material between them.

2. In a stretcher frame, a rail formed of two parallel bars having co-acting gripping faces at their inner edges, one of said bars being formed of resilient sheet metal and having a shoulder at its outer edge adapted to be sprung into interlocking engagement with the other bar for holding said gripping faces in clamping engagement.

3. A stretcher rail, comprising a main bar formed of resilient metal having a flange disposed along one edge and having a shoulder at its other edge, and a plurality of shorter clamping bars adapted to be separately sprung into position between said flange and s oulder for clamping the edge of a sheet of material against said flange.

41. A. stretcher rail, comprising a main bar having a flange disposed along one edge thereof and having a shoulder at its other edge, and a plurality of shorter clamping bars each fitting between said flange and shoulder for clamping the edge of a sheet of material against said flange, said main bar and clamping bars being formed to interlock When in 130 clamping engagement with each other, and one of said bars being formed of resilient metal and being adapted to yieldingly engage the other for retaining said bars in such interlocking engagement.

5. In a stretcher frame, a rail comprising a pair of bars formed of resilient sheet metal and each being or channel shape with a pair of flanges extending toward the other bar, the flanges of one of said bars extending between those oi the other, and the flanges at one edge of said bars being adapted to be sprung into interlocking engagement for clamping a sheet of material between the flanges at the other edge, a second rail, and means adapted to force said rails apart to stretch a sheet of material between them.

6. A stretcher rail, comprising a main bar formed of resilient metal and having transversely disposed flanges along opposite edges of one face, a clamping bar adapted to be sprung into position between said flanges and having at one edge a flange adapted to eo-act with the adjacent flange of said main bar for gripping the edge of sh et of material between them, said flange of said clamping bar being perforated, and transversely disposed guide rod mounted on said main bar and ex-- tending through said flange of said clamping bar for securing said bars together, while permitting them to slide one upon the other, to carry said ripping flanges into and out of engagement with each other.

7. A stretcher rail, comprising a pair of bars formed of resilient sheet metal and each being of channel shape with a pair of flanges extending toward the other bar, the flanges of one of said bars extending between those of the other, the flanges at one edge of said. bars being adapted to be sprung into interlocking engagement for clamping a sheet of material between the flanges at the other edge, and guiding means interposed between said bars, being adapted to secure said bars together when the clamping flanges are separated and to guide said clamping flanges into coeperative engagement when said bars are being sprung into interlocking engagement.

8. A stretcher, comprising a pair of parallel rails suspended in horizontal position, one above the other, the upper rail comprising a main bar formed of resilient metal having transversel disposed flanges along its upper and lower edges, a clamping bar adapted to he sprung into position between the flanges of said main bar for clamping the edge of a sheet of material against one of the flanges of said main bar, and supporting means extending loosely downtmrdly through the upper flange of said main bar and being secured to the lower flange of said main bar, whereby the weight of the frame will be carried by said lower flange.

9. stretcher frame, comprising a pair of parallel rails spaced apart, one above the other, a plurality of braces connecting said rails and each adapted to force the rails apart for stretching a sheet of material secured between them, one of said rails comprising a continuous main bar and a series of shorter clamping bars for securing the fabric to said main bar, and the other of said rails comprising a series of main bars hinged together and free to bend at their joints about axes transverse to the plane of the sheet of 1naterial to permit said braces to be expanded separately.

Signed at Chicago this 10th day of January, 1908.

Hi RLES P. FREESTATE.

Witnesses E. A. RUMMLER, MARY M. DILLMAN.

It is hereby certified that in Letters Patent No. 914,261, granted March 2, 1909,

upon the application of Charles P. Freestate, of Chicago, Illinois, for an improvement in Stretcher-Frames, errors appear in the printed specification requiring correction,

as follows: In line 109, page 2, the words their inner should be stricken out and the Words adjacent longitudinal inserted instead; in line 11 1, same page, the period after the word engagement. should be stricken out and a comma and the following clause inserted: a second rail, and means adapted to force said rails apart to stretch a sheet of material between them; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Ofiice.

Signed and sealed this 6th day of April, A. D., 1909.

C. C. BILLINGS,

Acting Commissioner of Patents.

[SEAL] 

